(1) Field of the Invention
The invention relates generally to the field of calibration of instruments, and more particularly to systems and methods for calibrating accelerometers for use in connection with wave measurements in, for example, an ocean environment.
(2) Description of the Prior Art
An accelerometer generates an output signal which has an amplitude which is related to the acceleration that is applied to the accelerometer. It is often necessary to calibrate the accelerometer, that is, to determine the amplitude of its output signal as a function of the magnitude of the applied acceleration (the accelerometer's "signal profile") and of its frequency. If the accelerometer is used in an ocean environment, the accelerometer may undergo a generally oscillatory, sinusoidal-like vertical acceleration due to wave action. By determining the vertical acceleration a wave may apply to the accelerometer, the wave's amplitude statistics may be determined, which may, in turn, provide information as to the wind and other weather conditions.
Prior systems for calibrating accelerometers relied on comparisons of the accelerometers to certain standard devices. Such systems assumed that the standards themselves were properly calibrated and, in any case, the comparisons themselves could introduce additional error into the calibration of the accelerometers undergoing calibration.